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    <title>Document</title>
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    <script>
      
        var obj = {
            birth:1990,
            getAge:function(year){ //2015
                console.log(year);
                var fn = (y)=>{
                    console.log(y); // 2015
                    console.log(this,"this");
                  return  y-this.birth
                }
                return fn.call({birth:2000},year)
            }
        }
        console.log(obj.getAge(2015));

    </script>
</body>
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